Long-Term Side Effects of Klonopin Klonopin is used to prevent and manage seizures, panic disorders, and anxiety disorders. Discover the short- and long-term side effects of Klonopin. Article Contents What Is Klonopin (Clonazepam)? Klonopin (clonazepam) falls under a class of medication known as benzodiazepines and is approved for treating different types of seizures, certain movement disorders, and panic disorders. The drug is also known as an antiepileptic or anticonvulsant medication. Data between 2015 and 2016 found that 30.5 million people in the U.S. used